Then it all came crashing down. It was perhaps the nadir of this past World Cup cycle, really even before qualifying for the big show next summer actually began. All the bluster and dreaminess of the Jurgen Klinsmann regime was blown up in an instant at LP Field that night, and that’s when the real uneasiness began.

It’s been a long time since that moment. The coach that day, Caleb Porter, has rebounded, leading the Portland Timbers in what could be a historic season in his first year as a pro head coach. The US Under-20s’ failure at the U-20 World Cup last month is going down a bit easier, too, now that we’ve had time to understand what a horrific group into which they were drawn.

And most encouragingly, the senior US team is riding a wave of positivity, unbeaten in five straight World Cup qualifiers and on the cusp of booking a ticket to Brazil. This "1A" Gold Cup squad is also showing its stuff, three for three in the group stage and another three wins from winning back the trophy for the first time in six years.

But that feeling – huge promise, followed by an unexpected and flattening feeling of finality – it’s a theme we’ve felt too often as fans of U.S. Soccer. You can go down the list, and a few stick out: the 2009 Gold Cup and 2010 World Cup are some particularly stinging ones.

There was something about that Olympic squad that felt worse. It was a roster full of insanely talented youngsters, nearly all of whom were homegrown. It was a coming-out party for Porter, a gifted, attack-minded coach who'd dominated at the college level. And it was what was supposed to be the beginning of a new American footballing mentality taking its first steps on the world stage.

It started so well – there was the 6-0 pasting of Cuba. Then it got a little worrying in a surprising loss to Canada. Then it bottomed out against El Salvador.

That night in Tennessee’s capital still has a lot of ghosts to give up.

This current Gold Cup has been all about redemption stories. Landon Donovan and Stuart Holden returning to the national team, for instance, and perhaps staking claims on the eventual World Cup roster. Brek Shea scoring a winning goal after long spells in and out of camp. Chris Wondolowski getting of the schneid in a big way. Oguchi Onyewu finally getting healthy and then pulling up lame again.

But the story line for Sunday's quarterfinal (4 pm ET, Fox/Univision, live chat on MLSsoccer.com) may be the best. The trophy is the ultimate thing, of course. But once again, a US squad has shown wonderful promise over a brief period together, and now will face its first true test with something on the line.

That El Salvador is the opponent in Baltimore is really just a coincidence. The stakes, however, are not. An overwhelmingly pro-Salvadoran crowd will fill M&T Bank Stadium to cheer on La Selecta as they seek to ruin the American party yet again.

And the best part is that four players from that letdown in Nashville will be wearing US jerseys: Shea, Joe Corona, Mix Diskerud and Johnson.

Let’s be clear: This isn’t about revenge. It’s one angle, yes, and it’s a fun one. And it’s fitting that six guys on El Salvador’s roster were also on that U-23 squad that kept the US from going to London.

This is about burying a horrible memory for good. It’s about fulfilling the promise. It’s about getting a job done instead of folding. And it’s about acknowledging a past failure and learning from it.

The Redemption Song won’t truly be sung until the USMNT is hoisting that trophy in Chicago. But with a win on Sunday, at least the tune won’t be cut off in mid-verse.